Hi team, are there any examples of how to build a custom docker image as mentioned here to use CustomRunCoordinator with Helm chart?

It can be any Docker image as long as it has the dagster packages that you're referencing in your instance Often something like this:

RUN pip install \
    dagster==${DAGSTER_VERSION} \
    dagster-postgres \
    dagster-k8s \
    dagster-aws \
    dagit